Hey there anerinbraden,
Thanks for reaching out to the Apple Support Communities. We'd be happy to take a closer look into this with you.
Just to confirm, are you having issues with the microphones on your iPhone and accessories producing feedback when you talk, or are you experiencing sound issues from the speakers on your iPhone and headsets? Does this issue occur with all calls, or just calls with certain contacts? Does the same issue occur if you use your accessories with another device?
For help with troubleshooting issues with the microphones take a look at these resources that may help:
If the issue is with the speakers on your iPhone and accessories, check this next link instead: If you hear no sound or distorted sound from your iPhone, iPad, or iPod touch speaker - Apple Support
Let us know if that's able to help.
Take care.